From 950336ba3e4a1ffd2ca60d29f6ef386dd2c7351d Mon Sep 17 00:00:00 2001 From: Vladis Dronov Date: Wed, 23 Mar 2016 11:53:46 -0700 Subject: Input: ati_remote2 - fix crashes on detecting device with invalid descriptor The ati_remote2 driver expects at least two interfaces with one endpoint each. If given malicious descriptor that specify one interface or no endpoints, it will crash in the probe function. Ensure there is at least two interfaces and one endpoint for each interface before using it. The full disclosure: http://seclists.org/bugtraq/2016/Mar/90 Reported-by: Ralf Spenneberg Signed-off-by: Vladis Dronov Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov --- drivers/input/misc/ati_remote2.c | 36 ++++++++++++++++++++++++++++++------ 1 file changed, 30 insertions(+), 6 deletions(-) diff --git a/drivers/input/misc/ati_remote2.c b/drivers/input/misc/ati_remote2.c index cfd58e8..1c5914c 100644 --- a/drivers/input/misc/ati_remote2.c +++ b/drivers/input/misc/ati_remote2.c @@ -817,26 +817,49 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d ar2->udev = udev; + /* Sanity check, first interface must have an endpoint */ + if (alt->desc.bNumEndpoints < 1 || !alt->endpoint) { + dev_err(&interface->dev, + "%s(): interface 0 must have an endpoint\n", __func__); + r = -ENODEV; + goto fail1; + } ar2->intf[0] = interface; ar2->ep[0] = &alt->endpoint[0].desc; + /* Sanity check, the device must have two interfaces */ ar2->intf[1] = usb_ifnum_to_if(udev, 1); + if ((udev->actconfig->desc.bNumInterfaces < 2) || !ar2->intf[1]) { + dev_err(&interface->dev, "%s(): need 2 interfaces, found %d\n", + __func__, udev->actconfig->desc.bNumInterfaces); + r = -ENODEV; + goto fail1; + } + r = usb_driver_claim_interface(&ati_remote2_driver, ar2->intf[1], ar2); if (r) goto fail1; + + /* Sanity check, second interface must have an endpoint */ alt = ar2->intf[1]->cur_altsetting; + if (alt->desc.bNumEndpoints < 1 || !alt->endpoint) { + dev_err(&interface->dev, + "%s(): interface 1 must have an endpoint\n", __func__); + r = -ENODEV; + goto fail2; + } ar2->ep[1] = &alt->endpoint[0].desc; r = ati_remote2_urb_init(ar2); if (r) - goto fail2; + goto fail3; ar2->channel_mask = channel_mask; ar2->mode_mask = mode_mask; r = ati_remote2_setup(ar2, ar2->channel_mask); if (r) - goto fail2; + goto fail3; usb_make_path(udev, ar2->phys, sizeof(ar2->phys)); strlcat(ar2->phys, "/input0", sizeof(ar2->phys)); @@ -845,11 +868,11 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d r = sysfs_create_group(&udev->dev.kobj, &ati_remote2_attr_group); if (r) - goto fail2; + goto fail3; r = ati_remote2_input_init(ar2); if (r) - goto fail3; + goto fail4; usb_set_intfdata(interface, ar2); @@ -857,10 +880,11 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d return 0; - fail3: + fail4: sysfs_remove_group(&udev->dev.kobj, &ati_remote2_attr_group); - fail2: + fail3: ati_remote2_urb_cleanup(ar2); + fail2: usb_driver_release_interface(&ati_remote2_driver, ar2->intf[1]); fail1: kfree(ar2); -- cgit v1.1